The present invention relates to a device for removing plaster from a wall.
Devices for the removal of plaster from walls of the foregoing type include a housing having a hand grip and a supporting and a closing plates, and two oscillatory tool supports movable in opposite directions and positioned in the housing and supporting cutting tools for removing plaster from walls.
Devices of the type under consideration serve to flatten and/or shape the upper surface of the freshly plastered wall hours before the plaster is completely dried-up and hardened. This after-treatment of the plastered walls is particularly required when the plaster is mechanically sprayed onto the wall.
Devices for the mechanical removal of plaster from walls have been known. Such a device has been disclosed, for example in DE-PS No. 2453262. All known mechanical devices for removing plaster from the wall have, however the disadvantage which resides in that the manupulation of such devices is quite troublesome because in many cases the plaster sticks the hand scraper, and a considerable muscle effort is necessary to use the gripping board having the steel rods when the planing of the plaster layers is required. In the device disclosed in DE-PS No. 2453262 also the operation is difficult due to the use of the electric motor with the transmission connected thereto because the whole device must be held with two hands gripped on the two handgrips. Inasmuch as circular movements on the plastered surface must be performed an operator has to hold heavy weights with both hands. The operator must also work on a scaffold platform whereby working with two hands holding the heavy device becomes dangerous.
It has been also known that with hand-held mechanically operated devices for removing plaster from walls, for example cutting knives or hedge clippers, these devices must be provided with counter parts for compensating for occuring torques and for the compensation for force impulses appearing on the hand of the operator. These means can not, however, prevent substantial vibrations which result from the heavy weight of the device and thus prevent the fatigue and possible danger to the operator with the devices in which the operator must carry also the drive motor and the crank transmission or the like, by means of which a rotational movement of the motor is translated into the oscillating reciprocating motions.